ECHIDNIDE 125 
be included in two species, which, with some hesitation, are referred 
to two genera—Hechidna and Proechidna (Acanthoglossus). 
Echidna.i—In Echidna there are five toes, all of which are 
provided with claws, those of the fore feet being broad, slightly 
curved, and directed forwards, while the posterior ones are slender, 
more curved, and inclined outwardly. The beak is about as long 
as the rest of the head, and either nearly straight, or slightly curved 
upwards, while the palate is comparatively wide, and but slightly 
vaulted. The number of the vertebre is C 7,D 16, L 3,8 3, Ca 12. 
The one existing representative of the genus (Z. aculeata) occurs in 
New Guinea, Tasmania, and Australia. 
So much variation is displayed by this animal, that it has been 
divided into several species, but the latest researches tend to show 
that these variations cannot be regarded as indicating more than 
races, of which there are three well-marked types. 
The first race, or variety, has been termed the Port Moresby 
Echidna, and is only known from that Papuan locality. It is 
distinguished from the typical form by its smaller size, by the 
shorter spines on the back, which admit of the fur being seen, and 
by the more spinous covering of the head, belly, and limbs, as well 
as by the lighter skull and relatively larger beak. 
The typical variety is confined to the Australian mainland, and 
is of medium size. The spines of the back are very long and stout, 
often reaching a length of two inches, and almost completely con- 
cealing the hair. The colour of these spines varies from yellow at 
the roots to black at the tips, but some may be altogether yellow. 
The hair of the back is black or dark brown in colour, but it may 
be occasionally absent, or in the region of the loins may exceed the 
spines in length. The limbs and under surface of the body are 
covered with dark brown hair, thinly interspersed with short spines ; 
and the hair of the face is of the same general hue as that of the 
body. The skull has a slender rostrum and a flat and narrow 
brain-case. 
In the third or Tasmanian race, which is confined to Tasmania, 
the average size is somewhat larger than in the typical form. ‘The 
most characteristic feature is, however, the shortness of the spines 
of the back, which in the greater part of that region are almost or 
quite concealed by the hairs. The hairs of the back are dark 
brown, those of the under surface and sides of the head being 
generally rather paler. There is often a white spot on the chest. 
Very frequently there is a difference in the proportionate lengths 
of the hinder claws from those of the typical race. In the skull 
the beak is comparatively short and stout, and the brain-case large 
and wide. 
Echidnas are usually found in rocky districts, and more especially 
1 Cuvier, Tableau Elémentaire @ Hist. Nat. p. 148 (1798). 
